The Scarecrow is the alter ego of psychologist Dr. Jonathan Crane, as well as one of Batman's most dangerous adversaries.

Jonathan was taunted and bullied relentless in his youth, and he vowed to understand and overcome his fears. He decided to achieve this through studying psychology and biochemistry, but was kicked out of his university for experimenting on human subjects.

Adopting the identity of the Scarecrow, he armed himself with a hallucinogenic gas that induced fear into its subjects, making their greatest nightmares seem frighteningly real. Through his use of Batman's greatest weapon – fear –, he has become one of his most psychologically dangerous enemies. He teamed up with the mysterious Arkham Knight and the former assassin Deathstroke on his attack on Gotham at Halloween.

Scarecrow was the only villain in Arkham Asylum to not be announced before the game's release, as his appearance was intended to be a surprise. Conversely, he was the only villain from Arkham Asylum to not appear in Arkham City, as the developers knew they wanted him to be an important villain in Arkham Knight.

It is also worth noting that he does not appear in Arkham Origins either, likely because the developers did not want to interfere with his role in Arkham Knight.

The noose Scarecrow wears around his neck is likely inspired by his The New Batman Adventures appearance.

All of Scarecrow's attacks on Batman seem to prey on three of Batman's greatest fears.

The first attack seems to be connected to Batman's guilt over the lives he has been unable to save, as well his fear of failure.

The second attack is connected to the haunting memory of his parents' deaths.

The third attack is connected to Batman's unconscious fear that he might be just as crazy as the enemies he fights against.

The third Scarecrow attack breaks the fourth wall, in that it preys on a gamer's fear of their system crashing.